Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description adds substantial behavioral context: it fans out across multiple sources, soft-fails on USPTO patents, reports sources_used/sources_failed, returns resolved:false with a notes line for private companies, and clarifies that empty sections mean 'no data' rather than a bug. This goes far beyond the annotations and gives the agent a realistic model of what will happen when the tool is invoked.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is long, but almost every sentence carries distinct information: examples, accepted input forms, source fan-out list, resolved:false behavior, and soft-failure semantics. The front-end immediately conveys the core purpose, and the detailed notes are earned. It could be tightened slightly, but the density of useful guidance justifies most of the length.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Even without an output schema, the description tells the agent what to expect in the response: cik, company_name, resolved_from/resolved_to, recent_filings with URIs, fundamentals fields, per-source sections, sources_used/sources_failed, and the resolved:false behavior. It also covers edge cases like private companies, absent FDA products, and USPTO API sunset. This is unusually complete for a tool with no output schema and makes successful invocation and result interpretation highly likely.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Input schema coverage is 100%, so the baseline is 3. The description adds meaningful guidance beyond the schema: it clarifies that type='company' and type='ticker' are interchangeable, that value can be a ticker, zero-padded CIK, or company name, and that names resolve via SEC EDGAR's company-name match. It also gives examples of valid values ('AAPL', '0000320193', 'Moderna'), which helps an agent construct correct invocations.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb and resource: 'full cross-source profile of a US public company in ONE parallel call.' It enumerates the source types covered (SEC, XBRL, USPTO, USAspending, FDA Purple Book, DOL LCA, news, GLEIF) and provides concrete example queries ('Tell me about X', 'research Acme'). This clearly distinguishes it from narrower lookup tools and sibling tools like compare_entities or resolve_entity.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives explicit usage context: use when a user asks for a holistic view, and 'ALWAYS PREFER over chaining single-pack SEC/XBRL/news lookups.' It also explains what happens for private companies and empty sections, setting expectations for edge cases. It does not explicitly contrast against sibling tools like compare_entities or deep_research, but the 'holistic view of a single public company' guidance is sufficiently clear for an agent to choose this tool.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.